Based on NXP TEA1836XT + TEA1792T 65W NOTEBOOK ADAPTER SOLUTION

The TEA1836XT is suitable for power supplies up to 75 W and requires extended high peak power capability to provide high power without the need for power factor correction. Typical applications are notebook adapters, printers, televisions or computer monitors.

The TEA1836XT is a low cost switching power supply (SMPS) controller IC for flyback topology. The built-in green feature provides high efficiency at all power levels.

At lower power levels, the flyback operates in QR mode. When the power level is reduced, the controller switches to DCM or Frequency Reduction (FR) mode. The peak current is reduced to 25% of the maximum peak current.

At low power levels, the flyback converter switches to burst mode when the flyback switching frequency reaches 25 kHz. To ensure high efficiency at low power and excellent no-load power performance, a pulse mode is integrated to minimize photocurrent because the switching frequency in this mode is a minimum of 25 kHz and the pulse frequency is always below 800 Hz. The frequency is beyond the audible range.

In the non-switching phase of the burst mode, the internal IC supply current is reduced, further optimizing efficiency. The valley switch is used for all modes of operation.

The TEA1836XT includes Ultra Power Protection (OPP). OPP enables the controller to provide 150% peak power in excess power for a limited time (200 ms). If the output is shorted, the output power is limited to 100% to keep the average power consumption below 5W.

The TEA1836XT is implemented in a high voltage SOI (silicon on insulator) process. This process combines the advantages of low-pressure processes such as accuracy, high-speed protection and control while maintaining high-voltage capability such as high-voltage startup and integrated X-Cap discharge.

The TEA1836XT enables low cost, high efficiency and reliable power requirements up to 75 watts, making it easy to design and the minimum number of external components.

General features:

• DCM flyback controller IC for low-cost applications

• Wide supply voltage range (up to 30 V; 35 V peak allowed for 100 ms)

• Integrated high-voltage start-up current source

• Continuous minimum VCC regulation during start-up and protection via the HV pin, allowing a small VCC capacitor to be used

• Reduced optocoupler current (100uA) in burst mode, enabling low power consumption in no-load while keeping the output voltage in regulation

• Converter switching frequencies and burst mode operation outside the audible area

• Integrated active X-capacitor discharge

• Adjustable soft start

• Power-down mode activated by the PROTECT pin

• 150 % peak power capability

Green characteristics:

• Low supply current during normal operation (0.6 mA without driver load)

• Low supply current during non-switching state in burst mode (0.2 mA)

• Valley switching for minimum switching losses

• Quasi resonant controller can be used in combination with NXP Semiconductors SR controllers for optimal efficiency performance

Burst mode and frequency reduction mode with fixed minimum peak current to maintain high efficiency at low output power levels

Protection features:

• Mains voltage independent OverPower Protection (OPP)

• Internal OverTemperature Protection (OTP)

• Integrated overpower time-out

• Integrated restart timer for system fault conditions

• Continuous mode protection using demagnetization detection

• Accurate OverVoltage Protection (OVP)

• General-purpose input for latched protection; can be used for external OverTemperature Protection (OTP)

• Driver maximum on-time protection

TEA1836XT application:

Typical applications are notebook adapters, printers, TVs or computer monitors.